Exercise max_element raw-pointer rule

Co-authored-by: nunoplopes <2998477+nunoplopes@users.noreply.github.com>

Author: Copilot

tests/unit/max.cpp

@@ -1,6 +1,5 @@
 #include <algorithm>
 #include <cassert>
-#include <vector>
 
 int main() {
   int x1 = 1, x2 = 2, x3 = 10, x4 = 20;
@@ -11,8 +10,8 @@ int main() {
   int r4 = std::min(*p2, x3);
   int r5 = std::max(30, 40);
   assert(r1 + r2 + r3 + r4 + r5 == 56);
-  const std::vector<int> values{1, 7, 7, 3};
-  auto max = std::max_element(values.begin(), values.end());
-  assert(max == values.begin() + 1);
+  int values[] = {1, 7, 7, 3};
+  int *max = std::max_element(values, values + 4);
+  assert(max == values + 1);
   return 0;
 }

tests/unit/out/refcount/max.rs

@@ -52,15 +52,25 @@ fn main_0() -> i32 {
         .read())
     };
     assert!((((((r1 + r2) + r3) + r4) + r5) == 56));
-    let values: Value<Vec<i32>> = Rc::new(RefCell::new(vec![1, 7, 7, 3]));
+    let values: Value<Box<[i32]>> = Rc::new(RefCell::new(Box::new([1, 7, 7, 3])));
     let max: Value<Ptr<i32>> = Rc::new(RefCell::new(
         ({
-            let ___first: Ptr<i32> = (values.as_pointer() as Ptr<i32>);
-            let ___last: Ptr<i32> = (values.as_pointer() as Ptr<i32>).to_end();
-            max_element_0(___first, ___last)
+            let count = ((values.as_pointer() as Ptr<i32>).offset(4)).get_offset()
+                - (values.as_pointer() as Ptr<i32>).get_offset();
+            let max_index = PtrValueIter::new(&(values.as_pointer() as Ptr<i32>), count)
+                .enumerate()
+                .max_by(|(idx_a, val_a), (idx_b, val_b)| {
+                    val_a
+                        .partial_cmp(val_b)
+                        .unwrap_or(std::cmp::Ordering::Equal)
+                        .then_with(|| idx_b.cmp(idx_a))
+                })
+                .map(|(idx, _)| idx)
+                .unwrap_or(0);
+            (values.as_pointer() as Ptr<i32>) + max_index
         }),
     ));
-    assert!((*max.borrow()) == (values.as_pointer() as Ptr<i32>).offset(1_i64 as isize));
+    assert!((*max.borrow()) == (values.as_pointer() as Ptr<i32>).offset(1));
     return 0;
 }
 pub fn __cpp2rust_init_globals() {}

tests/unit/out/unsafe/max.rs

@@ -49,13 +49,21 @@ unsafe fn main_0() -> i32 {
         })
     };
     assert!(((((((r1) + (r2)) + (r3)) + (r4)) + (r5)) == (56)));
-    let values: Vec<i32> = vec![1, 7, 7, 3];
-    let mut max: *const i32 = (unsafe {
-        let ___first: *const i32 = values.as_ptr();
-        let ___last: *const i32 = values.as_ptr().add(values.len());
-        max_element_0(___first, ___last)
+    let mut values: [i32; 4] = [1, 7, 7, 3];
+    let mut max: *mut i32 = (unsafe {
+        let count = values.as_mut_ptr().add(4).offset_from(values.as_mut_ptr()) as usize;
+        std::slice::from_raw_parts(values.as_mut_ptr(), count)
+            .iter()
+            .enumerate()
+            .max_by(|(idx_a, x), (idx_b, y)| {
+                x.partial_cmp(y)
+                    .unwrap_or(std::cmp::Ordering::Equal)
+                    .then_with(|| idx_b.cmp(idx_a))
+            })
+            .map(|(i, _)| values.as_mut_ptr().add(i))
+            .unwrap_or(values.as_mut_ptr())
     });
-    assert!(max == values.as_ptr().add(1_i64 as usize));
+    assert!(max == values.as_mut_ptr().add(1));
     return 0;
 }
 pub unsafe fn __cpp2rust_init_globals() {}